The final stage of gout, characterized by crystalline deposits in cartilage, synovial membranes, and soft tissue, is called a. complicated gout. b. gouty arthritis. c. asymptomatic hyperuricemia. d. tophaceous gout.

The correct option is : d. tophaceous gout.

Explanation:

Tophaceous gout is the final and the third chronic stage of this disease. It is generally characterized by the inability to excrete uric acid, thus expanding urate pool. This results in the deposition of monosodium urate crystals, called tophi, in the cartilage, synovial membranes, soft tissues and tendons.

This characteristic crystalline deposits of monosodium urate crystals are not associated with the complicated gout. Whereas, the asymptomatic gout and the hyperuricemia gout does not result in deposition of crystals.